The mammalian ovary : Concerns about evaluation of prenatal environmental exposures

This work was supported by the European Union’s Horizon 2020 FREIA project (grant 277 agreement No. 825100). The authors declare no conflicts of interest regarding this study.Peer reviewedPostprin

Field desorption ion source development for neutron generators

A new approach to deuterium ion sources for deuterium-tritium neutron generators is being developed. The source is based upon the field desorption of deuterium from the surfaces of metal tips. Field desorption studies of microfabricated field emitter tip arrays have been conducted for the first time. Maximum fields of 30 V/nm have been applied to the array tip surfaces to date, although achieving fields of 20 V/nm to possibly 25 V/nm is more typical. Both the desorption of atomic deuterium ions and the gas phase field ionization of molecular deuterium has been observed at fields of roughly 20 V/nm and 20-30 V/nm, respectively, at room temperature. The desorption of common surface adsorbates, such as hydrogen, carbon, water, and carbon monoxide is observed at fields exceeding ~10 V/nm. In vacuo heating of the arrays to temperatures of the order of 800 C can be effective in removing many of the surface contaminants observed

Analysis of Clean Transition Metal Surfaces by Core Level Spectroscopy

The shifts in the binding energy of core electrons detected by high resolution X-ray photoelectron spectroscopy are a very sensitive probe of the chemical bonding of the excited atom. Since the surface atoms have their geometrical environment perturbed, their core levels are shifted from their bulk positions. A very large number of experiments have been performed on the 4f core level positions of tantalum and tungsten for various orientations of the surface plane. Systematic trends have been put forward and explained by theoretical models. Furthermore, the analysis of the angular variation of the core level line intensities gives structural information when compared with theoretical calculations. In the case of W(100) a single scattering theory is sufficient to reproduce experimental data. Finally we show that, in some particular cases, the core level lineshapes may differ strongly from a Doniach Sunjic model. The temperature dependence of their widths due to core hole-phonon coupling can be reproduced within the independent boson theory

Maternal exposure to ambient black carbon particles and their presence in maternal and fetal circulation and organs : an analysis of two independent population-based observational studies

Funding European Research Council, Flemish Scientific Research Foundation, Kom op Tegen Kanker, UK Medical Research Council, and EU Horizon 2020. Acknowledgments The ENVIRONAGE birth cohort was initiated by the European Research Council (ERC-2012-StG 310898) and received additional funding from the Flemish Scientific Research Foundation and Kom op Tegen Kanker (KoTK). The detection equipment was funded by the METHUSALEM Program and the INCALO project (ERC-PoC). We acknowledge the Flemish Scientific Research Foundation (FWO; 1150920N to EB and G082317N). The SAFeR study was funded by the UK Medical Research Council (MR/L010011/1 and MR/P011535/1) and the EU's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie project PROTECTED (grant agreement number 722634) and FREIA project (grant agreement number 825100) as well as by NHS Grampian Endowments grants (16/11/056, 17/034, 18/14, 19/029, and 20/031) to PAF. We thank the midwives from the maternity ward of the East-Limburg Hospital in Genk, Belgium, for coordinating and supporting the study at the ward. We thank the Advanced Optical Microscopy Centre for the maintenance of the microscopic instruments. Moreover, we thank our colleagues from the Centre for Environmental Sciences for their hard work in collecting and processing the samples for the ENVIRONAGE birth cohort. Additionally, we thank the NHS Grampian Research Nurses and NHS Grampian R&D for their tireless recruitment work for the SAFeR study. We thank the past and present SAFeR team for their hard work with the fetuses and placentae. Finally, we thank the NHS Grampian Biorepository for their oversight role in SAFeR and assistance in processing and preparation of tissue sections.Peer reviewedPublisher PD

Novel nickel nanoparticles stabilized by imidazolium-amidinate ligands for selective hydrogenation of alkynes

[EN] The main challenge in the hydrogenation of alkynes into (E)- or (Z)-alkenes is to control the selective formation of the alkene, avoiding the over-reduction to the corresponding alkane. In addition, the preparation of recoverable and reusable catalysts is of high interest. In this work, we report novel nickel nanoparticles (Ni NPs) stabilized by three different imidazolium-amidinate ligands (ICy center dot(NCN)-N-(Ar); L1: Ar = p-tol, L2: Ar = p-anisyl and L3: Ar = p-ClC6H4). The as-prepared Ni NPs were fully characterized by (HR)-TEM, XRD, WASX, XPS and VSM. The nanocatalysts are active in the hydrogenation of various substrates. They present a remarkable selectivity in the hydrogenation of alkynes towards (Z)-alkenes, particularly in the hydrogenation of 3-hexyne into (Z)-3-hexene under mild reaction conditions (room temperature, 3% mol Ni and 1 bar H-2). The catalytic behaviour of Ni NPs was influenced by the electron donor/acceptor groups (-Me, -OMe, -Cl) in the N-aryl substituents of the amidinate moiety of the ligands. Due to the magnetic character of the Ni NPs, recycling experiments were successfully performed after decantation in the presence of an external magnet, which allowed us to recover and reuse these catalysts at least 3 times preserving both activity and chemoselectivity.The authors thank CNRS, UPS-Toulouse, INSA, "IDEX/Chaires d'attractivite l'Universite Federale Toulouse Midi-Pyrenees", "Instituto de Tecnologia Quimica" (ITQ; UPV-CSIC), "Juan de la Cierva" programme (IJCI-2016-27966), "Primero Proyectos de Investigacion" (PAID-06-18), "Instituto de Investigaciones Quimicas" (IIQ; CSIC-US), "Ministerio de Ciencia, Innovacion y Universidades" (MCIU/AEI), FEDER funds of the European Union (PGC2018-095768-B-I00) and ERC Advanced Grant (MONACAT 2015-694159) for financial support. We also thank L. Datas for the TEM facilities (UMS Castaing) and S. Cayez for the HRTEM measurements.López-Vinasco, AM.; Martínez-Prieto, LM.; Asensio, JM.; Lecante, P.; Chaudret, B.; Cámpora, J.; Van Leeuwen, PWNM. (2020). Novel nickel nanoparticles stabilized by imidazolium-amidinate ligands for selective hydrogenation of alkynes. Catalysis Science & Technology. 10(2):342-350. https://doi.org/10.1039/c9cy02172hS342350102Swamy, K. C. K., Reddy, A. S., Sandeep, K., & Kalyani, A. (2018). Advances in chemoselective and/or stereoselective semihydrogenation of alkynes. Tetrahedron Letters, 59(5), 419-429. doi:10.1016/j.tetlet.2017.12.057Lei, J., Su, L., Zeng, K., Chen, T., Qiu, R., Zhou, Y., … Yin, S.-F. (2017). Recent advances of catalytic processes on the transformation of alkynes into functional compounds. Chemical Engineering Science, 171, 404-425. doi:10.1016/j.ces.2017.05.021J. G. de Vries and C. 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